Voltage drop at starter

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92yukon

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I know this is brought up frequently and I have read through similar threads , but here’s where I’m at if anyone can help.

Truck is new to me and was starting fine until yesterday. I was just test driving it around my neighborhood and it cut off, went to restart it and just a click, tried to jump it and same thing. Grabbed my new XS Power battery out my car and tossed it in this time cranks very slow but no start.

So today I have replaced both ground straps and cleaned connection points, replaced ground cable from the battery to block and battery to fender and cleaned all connection points. Replaces battery cable from battery to starter, battery to alternator, and battery to fuse block. After all that the truck does the exact same thing very slow crank and will not start.

I did have the starter tested this morning but I was not confident in the young lady working at autozone but it did test good, went to Napa for conformation but apparently that location does not due starter testing.

I took a video (not sure how to post it here) of my voltage using a fluke 77 multimeter, I’m at 13v, 12.6v key on and drops to low 8v cranking. Where should I go from here ?
 

Scooterwrench

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Does the starter cable get hot when you're cranking it? Many bad starters will pass a no load test but won't turn the motor over. Usually the cable will get really hot because of the increased current flowing.
 

92yukon

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Does the starter cable get hot when you're cranking it? Many bad starters will pass a no load test but won't turn the motor over. Usually the cable will get really hot because of the increased current flowing.
I just tried to crank it over twice and then grabbed the cable and battery terminal and neither seemed to have warmed up any.
 

92yukon

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You may have a bad cable.
All the cables I mentioned today were changed out with brand new cables and ends. Most are thicker than what came off, are there any I may have missed ? I have access to good automotive grade wiring so changing them out is no issue.
 

GoToGuy

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Have had the battery checked for load capacity? Can show relative good voltage but will not carry a load. New to you vehicle , no history known could have failing battery. With all new wires, clean ground 's ,. Starter or battery.
 

Schurkey

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The starting/charging power team is so interconnected that it's pointless to diagnose one part without also checking all the other parts. And--for the record--"Off-the-car" testing is almost but not quite useless. If the part fails the test, you can be reasonably sure the part is defective. If the part passes the test, you have to assure that the part was tested PROPERLY, THOROUGHLY, and the results interpreted correctly.

You need to verify the alternator including regulator, battery, starter, and all the cables connecting them. Which means "on-the-car" testing.

This used to be a common procedure, but I think it's slipped out of favor for reasons I don't understand.
 

92yukon

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I didn't want to throw parts at it but I'm thinking the starter is the weak link in the equation. Battery is good for sure
 
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